Business Insider: The payments industry had a huge year in 2014 and it’s showing no sign of slowing down. On the one hand tech giants like Amazon and Apple released new products that affirmed their long-term payments ambitions (Apple Pay and Amazon Local Register). On the other hand startups such as Stripe and ShopKeep continued to carve out market share, challenging older players like PayPal and VeriFone.

Understanding this complex and rapidly evolving space can be challenging. In a new explainer, BI Intelligence offers a high-level look at the payments industry – how it functions, who the key players are, and the trends shaping the industry. We start by explaining payment-card processing, since the majority of consumer payments and transaction volume flow through this system. From there we take a look at how consumers’ move to mobile devices is changing the way we pay, and which players stand to benefit.